首页
登录
职称英语
What happened to the London underground railway about three decades ago? [br] [
What happened to the London underground railway about three decades ago? [br] [
游客
2023-11-22
64
管理
问题
What happened to the London underground railway about three decades ago? [br]
The world’s first completely automatic railway has been built under the busy streets of London. The railway is called the Victoria Line, and it is part of the complete London underground railway.
The new Victoria Line was opened in 1969. This new line was very different from the others.
The stations on the other lines need a lot of workers to sell tickets, and to check and to collect them when people leave the trains. This is all different of the Victoria Line. Here a machine checks and collects the tickets, and there are no workers on the platforms.
On the train, there is only one worker. If necessary, this man can drive the train. But usually he just starts it; it runs and stops by itself. The trains are controlled by electrical signals which are sent by the so-called "command spots". The command spots are the same distance apart. Each sends a certain signal. The train always moves at the speed that the command spots allow. If the command spot sends no signals, the train will stop.
Most of the control work is done by computers. The computers also fix the train’s speeds, and send the signals to the command spots.
Other machines make sure that the trains are always a safe distance apart. If one train stays too long at a station, the other trains will then automatically move slower. So there is no danger of accidents on the line.
选项
A、It will stop automatically.
B、It will move on at the same speed.
C、It will gradually slow down.
D、It will keep a safe distance from the other trains.
答案
A
解析
转载请注明原文地址:http://tihaiku.com/zcyy/3210516.html
相关试题推荐
Eveniftheyproducednootherpositiveresult,theattacksontheLondonUnde
PassageThree(1)Givenallthathashappenedonsomanycampusesover
PassageThree(1)Givenallthathashappenedonsomanycampusesover
PassageThree(1)Givenallthathashappenedonsomanycampusesover
PassageThree(1)LondonmaybeEurope’scommercialcapital,butnotall
PassageTwo(1)Overthepastfewdecades,youngwomenhavebeenclimbi
PassageTwo(1)Overthepastfewdecades,youngwomenhavebeenclimbi
PassageTwo(1)Overthepastfewdecades,youngwomenhavebeenclimbi
Overthepasttwodecades,countriesintheworldhavebecomemoreandmore
Overthepasttwodecades,countriesintheworldhavebecomemoreandmore
随机试题
______doyouthinkofyourEnglishteacher?A、HowB、WhichC、WhatC“whatdoyout
Rabbitsarequietanimals,()theyareabletomake20differentsounds.A、howB、i
TV,Internetandradioareverypopularnowadays.Somepeoplesaythattheywi
SubfieldsofLinguisticsTheoverlappinginterestsbetweenthefieldoflinguist
WhatarethetwothingsthatAmericanpeoplecan’tavoid?______and______.[br
[originaltext]Threeyearsago,PunchaMaya,herhusbandandfivechildrenl
对于不领取施工许可证的建设工程,建设单位应当将保证安全施工的措施报送政府有关行政
下列关于事故、危险的说法正确的是( )。A.危险是事故的前兆,只有在一些触发事
询问调查法不包括( )。A:访问调查 B:邮寄调查 C:座谈会 D:实验
在宏观层面上,社会评价的目的包括()。A.促进不同地区之间的公平协调发展
最新回复
(
0
)